Laptop Notes

Partitioning

This is an EFI enabled Laptop. First you have to disable the UEFI secure boot at the startup of the computer. Press “esc” key at startup. In alternative you can also switch to legacy BIOS mode although it will be a hassle to boot Win8 anymore. Let's talk about disabling secure boot.

When you try to disable secure boot in the UEFI-mode in the BIOS of an Acer Travelmate P253-E with pre-installed Windows 8. The Secure Boot option is just gray and could not be reached with up/down keys. With secure boot enabled, the attempt to install Ubuntu 13.04 from LiveCD ended with the message: “DVDRAM has been blocked by the current security policy”and I could not boot the LiveCD. One way around is to set a UEFI-bios password in you UEFI-bios menus then you can disable the secure boot and keep uefi…

To avoid any anoyance, I created the folowing partitionsdoing manual partition:

Brightness adjustment

The brightness adjustment (FN+ left/right arrow) is apparently increased/decreased in two steps for one key press and has no effect on the screen brightness. The track pad does not recognize the right click.

First open a terminal window (digit Alt+Ctrl+T) and type :

sudo gedit /etc/default/grub
This will open the grub configuration file. (Grub is the initial boot selection software)
To be able to set the brightness, You've got to modify the line:

“acpi_osi=Linux” indicates that you are running Linux so the hardware behaves acordingly if it has been programed to.
“acpi_backlight=vendor” gives the priority to the acer_acpi module over the stock acpi. The stock acpi doesn't know how to manage brightness
You can also add the folowing parameters to save battery but at your own risk :

“pcie_aspm=force” sets the Active-State Power Management (ASPM) to save power in the Peripheral Component Interconnect Express (PCI Express or PCIe) subsystem by setting a lower power state for PCIe links when the devices to which they connect are not in use. This means your USB pointer will not allways work when your computer is not on power.
“i915.semaphores=1” Semaphores are not enabled by default on all generation of graphics cards. Enablement of semaphores solves several stability issues on Ivy Bridge graphics cards, such as GPU hangs, and improved stability and performance on Sandy Bridge generation of graphics cards. The drawbacks are occasional stability issues on some systems with VTd enabled. Semaphores can be enabled manualy via the i915.semaphores=1 kernel parameter.
“elevator=noop” The Linux kernel has various ways of optimizing disk I/O. One method it uses to help speed I/O reorders requests to the disk so that when the head moves across the disk it can service those requests in an orderly, sequential manner, rather than going back and forth a lot. This is known as an “elevator,” since it’s basically what an elevator does, too. An elevator doesn’t drop people off at floor 11, then 2, then 5, then 3. Instead, it drops people off in order: 2, 3, 5, 11. Same with I/O to disks.
Save and close the file and digit in the terminal window :

sudo update-grub
This will tell grub to reconfigure with the modified configuration file. Restart your laptop and you should be able to adjust the brightness with the hotkeys, you can go so low that the screen is completely black. (Thanks Florian)

Don't forget to disable the automatic brightness dimming of the screen by going into “system settings” > “Screen”
When dimming the screen, it goes so dark you can't see it and it doesn't go back on when you hit a key.

Reduce laptop screen brightness persistently

(tip by user esteban1uy)
You can change screen brightness in the Screen settings dialog, but it won't be persistent, you must repeat it every time your boot up your laptop. This has bugged many users. There are two methods

First method : Manual method

Thanks to esteban for pointing to a relatively easy fix.

Create a start-up script to reduce brightness by typing in a terminal:

gedit ~/.lowerbrightness.sh
… and paste this into the opened empty document:

#!/bin/sh
#change brightness setting on startup or resume
pkexec /usr/lib/gnome-settings-daemon/gsd-backlight-helper –set-brightness 488
… BUT! change the the last digit to a number relevant to you. I've put ”–set-brightness 488” to get a ca. 50% brightness setting (the maximum brightness value is 976). If you want e.g. 75% screen brightness, set the number to 3/4 of your max_brightness number (only give whole numbers, no “324,5”!). You get the idea. That done, save and exit.

Go to the file manager and right-click on your newly created ”.lowerbrightness.sh” file (it may be hidden, press CTRL+H to see it in your home directory), select Properties and in the Permissions tab make the file executable with a tick in “Allow executing file as program” - this is important or it won't work. Lastly, run the following command (replace USERNAME with your user name):